Plastified and rigid polyvinyl chloride compositions are known to be modified by addition of various additives in order to obtain the desired property profile. Known PVC compositions can be thermoformed and are suitable for a wide variety of applications, for example as packaging films, shrink films, and rigid films. Modification of PVC film is achieved by adding modifiers to improve impact resistance and to improve heat resistance, processing aids to improve processability and to improve the output of the production plant, lubricants to improve gelling behavior during manufacture, flow aids to improve thermoformability and orientability, matting agents to reduce gloss, and the like. The proportions by weight of the individual additives are, as a function of the requirement, from 0.1 to more than 40% by weight. The flowability and orientability of polyvinyl chloride compositions are preferably improved by using vinyl chloride copolymers.
EP-0 172 479 B1 discloses a film with a matt and rough surface, based on vinyl chloride polymers and on fillers. Lubricants and heat stabilizers are also added to this film. The filler used comprises starch making up from 1 to 15% by weight, based on the total weight of the film material. By virtue of this filler, good mattness and roughness together with minimum internal haze is achieved in polyvinyl chloride films based on vinyl chloride polymers with a fairly wide range of molecular weights. Vinyl chloride polymers that can be used here are vinyl chloride homopolymers or vinyl chloride copolymers, these having been prepared by one of the conventional polymerization processes, namely by emulsion polymerization, suspension polymerization, or bulk polymerization. The proportion of the comonomers in the copolymers is generally at most 20% by weight, based on the copolymer.
DE Auslegeschrift 27 16 853 discloses a film with a matt and rough surface which is composed of a vinyl chloride polymer, of a stabilizer, and of a lubricant, and which has been produced by a rolling-bank calendering process. The average molecular weight of an amount of from 10 to 40% by weight of the vinyl chloride polymer is from 110 000 to 190 000 and the average molecular weight of an amount of from 60 to 90% by weight of the vinyl chloride polymer is from 45 000 to 75 000, the weights always being based on the entirety of vinyl chloride polymer. The stabilizer is one selected from the group of the tin stabilizers, and the lubricant is one selected from the group of montanic esters, stearic acid, bisstearylethylenediamine, bispalmitoylethylenediamine, and glycerol oleate, the amount of stabilizer being from 0.5 to 2% by weight and the amount of lubricant being from 0.1 to 2% by weight, in each case based on vinyl chloride polymer. The modifier for impact resistance is one selected from the group of the acrylonitrile-butadiene-styrene, methyl methacrylate-butadiene-styrene, and methyl methacrylate-acrylonitrile-butadiene-styrene polymers, in an amount of from 3 to 15% by weight, based on vinyl chloride polymer.
EP1066339B1 describes a process for production of a film or of a sheet composed of a polyester resin composition by calendering. The polyester component of the resin is an amorphous or semicrystalline polyester whose crystallization half-life time from a molten state is at least 5 min. The polyester component is composed of at least 80 mol % of a diacid-radical component, of from 80 to 100 mol % of a diol-radical component, and from 0 to 20 mol % of a modifying diol. The diacid-radical component is based on 100 mol % of diacid radical, and the diol radical is based on 100 mol % of diol radical. The resin composition includes an additive which is an internal lubricant or antislip agent or a mixture thereof. The amount of the additive added is from 0.01 to 10% by weight, based on the total weight of the resin composition.
Surprisingly, amorphous or semicrystalline polyester resin compositions of this type are suitable for calendering with the aid of conventional calendering processes for production of uniform films or sheets. Polyester resin compositions of this type are marketed as Tsunami® by Eastman Chemical Corp., Tennessee, USA. The polyester compositions are usually used for production of polyester films, being base polymers generally making up more than 96% by weight, based on the total weight of the polyester films.
Modifiers used in conventional PVC films comprise conventional polymers composed of acrylonitrile-butadiene-styrene, methyl methacrylate-butadiene-styrene, methyl methacrylate-acrylonitrile-butadiene-styrene, methyl methacrylate and chlorinated polyethylene, polymethyl methacrylate and ethylene-vinyl acetate as impact-resistance components in an amount of from 1 to 20% by weight, based on the weight of the PVC film. Usual lubricants in PVC molding compositions from which PVC films are produced are fatty acids, fatty alcohols, fatty acid amides, metal soaps, esters of fatty acids with mono- or polyhydric alcohols, esters of dicarboxylic acids with mono- or polyhydric alcohols, esters of fatty acids and dicarboxylic acids with polyhydric alcohols, the substances known as mixed esters or complex esters, esters of phthalic acid with mono- or polyhydric alcohols, or natural or synthetic waxes. The amount of lubricants is from 0.1 to 2%, based on the total weight of the molding composition. Known heat stabilizers are tin stabilizers, in particular tin carboxylates, tin mercaptides, and tin dioglycolates. It is also possible to use metal stabilizers based on calcium, zinc, barium, cadmium, and to use other metal-free organic stabilizers and inorganic stabilizers, examples being chlorine scavengers based on dihydrotalcite. The proportion of heat stabilizers is generally from 0.3 to 5% by weight, based on the total weight of the molding composition.